Classical homeopathy is a 200-year old system of complementary and alternative medicine (CAM), which claims that a substance that can cause symptoms in a healthy person (provings) can cure similar symptoms in a sick person (Law of Similars). In a design synthesizing homeopathic provings, health psychology, and psychophysiological methodologies, this revised 3-year R21 exploratory study (NCCAM PAR 03-153) will assess the effects of two different homeopathic, plant-derived remedies ([A]: Nux Vomica 30c or [B]: Coffea Cruda 30c) on polysomnographic sleep recordings of adult human subjects of both sexes (N=60). Primary Specific Aims are: I. To evaluate the effects of two different active homeopathic remedies versus placebo on standard sleep stages and spectral EEG in human subjects; and II.To determine the effects of two different active homeopathic remedies versus placebo on nonlinear characteristics of sleep EEG in human subjects; The Secondary Aim is: III. To assess the contribution of baseline individual difference traits and subjective expectation in modifying the physiological outcomes above. The study will examine the interaction of the remedy effects with two different human personality traits associated with insomnia and overlapping those of persons reported in classical homeopathy to respond most strongly to each remedy. Subjects will fall into two subclinical groups of otherwise healthy persons: (i) those who score high on the personality trait of hostility (Type A/coronary-prone; contained within remedy picture of Nux Vomica)(n=30) and (ii) those who score high on the personality trait of anxiety sensitivity (panic-prone; contained within remedy picture of Coffea Cruda)(n=30). All subjects also will report insomnia from drinking coffee (a symptom common in homeopathy to both remedy types) and will replace it with a non-coffee caffeinated beverage for at least 7 days before and for the duration of the study (beverage coffee is reportedly a clinical antidote for many homeopathic remedies). During the 4-week protocol, on the first two nights of each study week, they will undergo at home, all-night polysomnographic sleep recordings, i.e., on days 1 and 2 (baseline 1), 8 and 9 (placebo), 15 and 16 (baseline 2), and 22 and 23 (remedy [A] OR remedy [B]). All will receive placebo at bedtime on day 8, single-blind (placebo given before any remedy to eliminate risk of carry-over effects and/or experimenter intentionality on placebo responses, problems reported in previous homeopathic provings). At bedtime on day 22, half of the subjects from each personality type will receive one dose of Nux Vomica and half will receive one dose of Coffea Cruda on a randomized, double-blind basis. All participants will also record subjective sleep and symptom patterns over the 4 weeks. Statistical analyses will include hierarchical linear models and general linear models. The chosen remedies in 30c doses each showed specific and different effects on sleep electroencephalograms of healthy animals in previous studies. This study will contribute to our long-range goal of understanding the neurophysiological and biopsychosocial mechanisms of classical homeopathic remedy treatment in patients with specific clinical conditions.